Stulak, John M.

Highly specialized left ventricular assist device care is not readily available in many areas, potentially limiting access to therapy. This retrospective analysis examines the relationship of outcomes by patient distance from implanting left ventricular assist device center within the Mechanical Circulatory Support Research Network. Zip codes were used to calculate patient distance, with the primary outcome of interest being 3-year survival by distance from the surgical center. Secondary outcomes included 90-day survival and incident event rates for the following: gastrointestinal bleeding, infection, cerebral event, and pump thrombosis. Across the four centers, there were 1184 patients supported for a median of 486 days. Overall survival was 91 ± 0.8% at 90 days and 61 ± 1.9% at 3 years, with worse 3-year survival in those living >90 vs . ≤90 miles from the ventricular assist device implant center (55 ± 3.0% vs . 64 ± 2.5, p = 0.019). Patients living >90 miles from an implant center were older, more likely to be implanted for destination therapy support, had a prior sternotomy, and had worse renal function than those living closer ( p <0.05 for all). After adjusting for these factors, albumin and center of implant, the hazard ratio did not reach statistical significance (hazard ratio = 1.2; p = 0.14). Except for gastrointestinal bleeding, the event rates for the secondary outcomes were higher for those living closer to the implanting center. Protocols should be designed for more frequent follow-up and increased shared care opportunities to ensure optimal outcomes are achieved in distant patients.

Continuous-flow left ventricular assist devices (CF-LVADs) have revolutionized the management of patients with advanced heart failure. Alternative implant strategies are increasingly used for device placement. We reviewed our experience from the Mechanical Circulatory Support Research Network registry with the HeartWare centrifugal CF-LVAD (HVAD). From May 2004 to August 2015, 1,150 patients underwent primary CF-LVAD implantation at our institutions. Within this group, a total of 283 patients (25%) were implanted with the HVAD. A minimally invasive left lateral thoracotomy (MILT) implant strategy was used in 53 patients (20%), of which 22 (42%) were implanted off-pump. Median age at implant was 59 years and 183 patients (65%) were implanted as bridge-to-transplantation. Follow-up was 100% complete for a total of 302 patient-years of support. In-hospital mortality was 4.9% (14 patients), and was comparable between the conventional sternotomy (CS) and MILT cohorts (p = 0.15). Patients in the MILT cohort had a shorter median length of stay (p < 0.01) and had a lower incidence of postimplant pump thrombus (p = 0.02). Cumulative survival at the end of follow-up reached 84%, and was comparable between the two groups (p = 0.298). Multivariate analysis identified preoperative bilirubin level as the only independent predictor of survival. Surgical technique had no impact on survival. In this large, multicenter experience, data demonstrate excellent survival and adverse event profiles for patients supported with the HVAD technology, regardless of surgical implant technique. With constant advancements in device technology along with our increasing clinical experience with the newer techniques, minimally invasive LVAD implantation continues to evolve as a valuable alternative to CS in selected patients.

Infection is a serious complication of left ventricular assist device (LVAD) therapy. However, an optimal antimicrobial surgical infection prophylaxis (SIP) regimen for LVAD implantation is not well established. We retrospectively reviewed all adults who underwent continuous-flow LVAD implantation from February 2007 to March 2015 at Mayo Clinic Rochester. Left ventricular assist device infection (LVADI) was defined using criteria published by the International Society for Heart and Lung Transplant. Patients excluded from the analysis included those who did not have HeartMate II or HeartWare device, patients with incomplete documentation of SIP, and those with an actively treated infection at the time of LVAD implantation. We compared risk of LVAD-specific and LVAD-related infections and all-cause mortality between SIP regimens at postoperative day 90 and 1 year using Kaplan–Meier time-to-event analyses. During study period, 239 adults underwent continuous-flow LVAD implantation at our institution where 199 patients received single-drug and 40 received multidrug SIP regimen. Median patient age was 62 years. Left ventricular assist device infection occurred in three patients (1.5%) in the single-drug group versus two patients (5.0%) in the multidrug group at 90 days (p = 0.4). There was no difference in infection-free (p = 0.4) and overall survival (p = 0.9) between two groups at 1 year. In conclusion, there was no clear benefit of using multidrug regimen as it did not impact infection-free survival or all-cause mortality compared with single-drug regimen. Prospective clinical trials are needed to further define the optimal SIP regimen for LVAD implantation.

Left ventricular assist devices (LVADs) are becoming a more frequent life-support intervention. Gaining an understanding of risk factors for infection and management strategies is important for treating these patients. We conducted a systematic review and meta-analysis of studies describing infections in continuous-flow LVADs. We evaluated incidence, risk factors, associated microorganisms, and outcomes by type of device and patient characteristics. Our search identified 90 distinct studies that reported LVAD infections and outcomes. Younger age and higher body mass index were associated with higher rates of LVAD infections. Driveline infections were the most common infection reported and the easiest to treat with fewest long-term consequences. Bloodstream infections were not reported as often, but they were associated with stroke and mortality. Treatment strategies varied and did not show a consistent best approach. LVAD infections are a significant cause of morbidity and mortality in LVAD patients. Most research comes from secondary analyses of other LVAD studies. The lack of infection-oriented research leaves several areas understudied. In particular, bloodstream infections in this population merit further research. Providers need more research studies to make evidence-based decisions about the prevention and treatment of LVAD infections.

Atrial fibrillation (AF) and tricuspid regurgitation (TR) are common in patients undergoing left ventricular assist device (LVAD) implantation. TR progression is associated with the presence of AF, and questions remain as to who benefits from tricuspid valve procedures (TVPs). We examined the impact of preoperative AF on TR progression after LVAD implantation. From February 2007 to May 2014, 250 patients underwent LVAD implantation at our institution. Patients with concomitant TVP were excluded from this analysis (113 patients). The indication for LVAD was destination therapy in 80 patients (58%) and the etiology of heart failure was ischemic in 73 (53%). Follow-up was available in all early survivors for a total of 393 patient-years of support. Of the 137 non-TVP patients, 52 (38%) had AF preoperatively. Observed overall survival at 1, 3, and 5 years was 82%, 67%, and 55%, respectively. Median grade of TR increased from 2 preoperatively to 3 (p = 0.04) in the AF group and 2.2 (p = 0.75) in the non-AF group at 5 years of follow-up. We also observed a significant difference in the degree of TR between groups at 3 months (p = 0.03) and 12 months (p = 0.01) postimplantation, and a trend toward significance at 18 (p = 0.06) and 24 (p = 0.07) months. The presence of AF is associated with early progression of TR after LVAD implantation. Addition of concomitant TVP in patients with preoperative AF may be considered in patients with less than severe TR. The impact of these findings on right ventricular failure/remodeling remains to be evaluated.

Although improvement in cardiac output and hemodynamic parameters is routinely demonstrated in patients implanted with continuous-flow left ventricular assist devices (CF-LVADs), improvement in exercise capacity is inconsistently seen. Our purpose was to determine whether native cardiac factors, LVAD factors, or comorbid factors were associated with lack of improvement. Review of all patients undergoing preimplant cardiopulmonary exercise testing (CPET) and CPET on LVAD therapy at one institution was performed between 2007 and 2014 (n = 49). Comprehensive assessment of echocardiographic parameters, right heart catheterization data, medications, and comorbid illness was undertaken. There was no mean improvement in peak oxygen consumption (VO2; 11.8–12.4 ml/kg/min; p = 0.26), although exercise time (5.1 [46% predicted] to 5.8 min [56% predicted]; p = 0.02) and nadir of the ratio of minute ventilation to carbon dioxide production slope (VE/VCO2; 39–36; p = 0.001) improved. Factors most strongly associated with improvement in VO2 were Heartmate II pulsatility index (PI; R = 0.48; p = 0.001), power (R = −0.40; p = 0.009), pump flow (R = −0.40; p = 0.008), and pump speed (R = −0.32; p = 0.04). Peak heart rate (HR) was also associated with improvement in VO2 (R = 0.41; p = 0.004). Left ventricular ejection fraction (LVEF; R = 0.004; p = 0.77), right ventricular (RV) function (R = 0.22; p = 0.28), and aortic valve opening (R = 0.20; p = 0.57) were not associated with improvement in VO2. Our data suggest that less reliance on LVAD support was modestly associated with improvement in exercise capacity. Further studies should seek to determine the optimal level of device support prospectively in relation to exercise capacity.

Redo aortic valve replacement (AVR) performed simultaneously with left ventricular assist device (LVAD) implantation carries potential for increased mortality rates. Although transcatheter AVR has been used for patients with previous LVAD placement, no literature reports concomitant valve-in-valve transcatheter AVR and LVAD implantation. Our patient had severe aortic prosthetic valve deterioration and advanced heart failure. Given the risks associated with reoperative aortic valve surgery, we chose transcatheter AVR at the time of LVAD implantation. Transthoracic echocardiography results showed severe aortic prosthetic valve deterioration with moderate aortic regurgitation as well as severe left ventricular dysfunction (ejection fraction, 11%). After redosternotomy, we performed transcatheter AVR via the ascending aorta and subsequent LVAD implantation. The postoperative course was uneventful. Generally, patients with structural deterioration of a bioprosthetic valve who report for LVAD therapy present considerable challenges to the surgeon. Concomitant transcatheter AVR offers a less-invasive alternative to surgical AVR that minimizes ischemic injury to myocardium.

Renal function improves early after left ventricular assist device (LVAD) implantation but later decline has been observed. We sought to determine the occurrence and evaluate possible causes for this decline. In 62 consecutive patients with HeartMateII LVAD with available calculated glomerular filtration rate (GFR, ml/min/1.73 m2) 1 year after implant, GFR was assessed repeatedly and possible predictors for decline from 3 to 12 months were investigated. Post-mortem renal specimens for patients supported with an LVAD were evaluated. GFR 54.5 ± 19.5 at admission increased to 66.4 ± 22.3 preoperatively and to 79.2 ± 30.1 ~1 month after implantation. Subsequently at ~3 months GFR declined to 74.7 ± 25.4, at ~6 months to 68.8 ± 23.1, and ~1 year after implant to 63.9 ± 17.7. Glomerular filtration rate at 1 year was significantly lower (p < 0.0001, p < 0.0001, p = 0.005) than GFR 1, 3, and 6 months after implant. Early rise in GFR after surgery was not associated with late decline. Shorter bypass time (β = −0.09, p = 0.048) and higher albumin 3 months after LVAD (β = 14.4, p = 0.025) were significantly associated with less later decline in GFR. Arteriosclerosis was identified in autopsy renal specimens. In conclusion, early gains in renal function after LVAD implant are not sustained in many patients. Patient, device, and operative factors may influence long-term renal function in these patients.

Background— Despite the ability of left ventricular assist device as destination therapy (DT-LVAD) to prolong survival for many patients with advanced heart failure, little is known about the eventual end-of-life care that patients with DT-LVAD receive. Methods and Results— All patients undergoing DT-LVAD at the Mayo Clinic in Rochester, Minnesota, from January 1, 2007, to September 30, 2014, who subsequently died before July 1, 2015, were included. Information about end-of-life care was obtained from documentation in the electronic medical record. Of 89 patients who died with a DT-LVAD, the median (25th–75th percentile) time from left ventricular assist device implantation to death was 14 (4–31) months. The most common causes of death were multiorgan failure (26%), hemorrhagic stroke (24%), and progressive heart failure (21%). Nearly half (46%) of the patients saw palliative care within 1 month before death; however, only 13 (15%) patients enrolled in hospice a median 11 (range 1–315) days before death. Most patients (78%) died in the hospital, of which 88% died in the intensive care unit. In total, 49 patients had their left ventricular assist device deactivated before death, with all but 3 undergoing deactivation in the hospital. Most patients died within an hour of left ventricular assist device deactivation and all within 26 hours. Conclusions— In contrast to the general heart failure population, most patients with DT-LVAD die in the hospital and few use hospice. Further work is needed to understand these differences and to determine whether patients with DT-LVAD are receiving optimal end-of-life care.